Modular cooling and heating systems

ABSTRACT

A module for use in a cooling and heating system includes an enclosure having a number of cartridge-receiving slots and at least one cartridge interchangeably disposed in one of the slots. The cartridge contains components for producing chilled fluid. The system can include a refrigerated load that is supplied with chilled fluid from the cartridge and a heat sink to which the cartridge rejects heat. The cooling and heating system can be configured to have at least one refrigeration circuit charged with a refrigerant and including a compressor, a condenser, an expansion device, and a heat exchanger, and at least one secondary cooling circuit charged with a coolant and including the heat exchanger, and a cooling coil. Heat is transferred from the coolant to the refrigerant in the heat exchanger. The system further includes a heating circuit for transferring heat from the condenser to a heating load.

BACKGROUND OF THE INVENTION

This invention relates generally to cooling and heating and moreparticularly to modular cooling and heating systems for use in manytypes of facilities.

Various commercial refrigerated fixtures, such as refrigerators,freezers, refrigerated display cases, walk-in storage coolers andfreezers, cold pans and wells, and the like, are widely used in manysettings. Restaurants, corporate office cafeterias, and other foodservice facilities, for example, typically have a number of refrigeratedfixtures located in food preparation areas and in food serving areas.Such food service facilities commonly use self-contained, stand alonerefrigerated fixtures, remote refrigerated fixtures (in which compressorsystems of individual refrigerated fixtures are placed in locationsremote from the fixtures at facility sites such as back rooms, roofs, orbuilding exterior areas), or a combination of self-contained and remotefixtures. Facilities using refrigerated fixtures typically also haverequirements for air conditioning, space heating and domestic hot waterheating.

Self-contained refrigerated fixtures have drawbacks when used in foodpreparation or serving areas as they are often noisy and reject heatinto the surrounding occupied eating or food preparation spaces, whichrejected heat often must be removed via facility air conditioningsystems. They also have very poor energy efficiency, and maintenance ofthe fixtures in food preparation and serving areas is difficult. Remoterefrigerated fixtures do remove the noise, heat rejection, and a portionof required refrigeration maintenance activities from the foodpreparation and serving areas, but still have relatively poorefficiency, require a substantial refrigerant charge, can be moredifficult to maintain and operate properly, and have much higher initialcost than self-contained fixtures. And while having generally betterenergy efficiency than self-contained fixtures, remote refrigeratedfixtures still have high energy consumption.

Accordingly, there is a need for a system that can efficiently andeconomically meet the refrigeration, air conditioning and heatingrequirements for many types of facilities.

SUMMARY OF THE INVENTION

The above-mentioned need is met by the present invention, one embodimentof which includes a module for use in a modular cooling and heatingsystem. The module includes an enclosure having a number ofcartridge-receiving slots, an electronic controller mounted to theenclosure, and at least one cartridge interchangeably disposed in one ofthe cartridge-receiving slots so as to make an electrical connectionwith the electronic controller. The cartridge contains components forproducing chilled fluid. The system can include a refrigerated load thatis supplied with chilled fluid from the cartridge and a heat sink towhich the cartridge rejects heat.

The cooling and heating system can be configured to have at least onerefrigeration circuit charged with a refrigerant and including acompressor, a condenser, an expansion device, and a heat exchanger allconnected together in series flow communication, and at least onesecondary cooling circuit charged with a coolant and including the heatexchanger, a pump, and a cooling coil all connected together in seriesflow communication. Heat is transferred from the coolant to therefrigerant in the heat exchanger. The cooling and heating systemfurther includes a heating circuit charged with a heat transfer fluidand including the condenser, at least one heating load, and another pumpfor circulating the heat transfer fluid between the condenser and theheating load. Heat is transferred to the heat transfer fluid in thecondenser, and heat is transferred from the heat transfer fluid to theheating load.

DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of a cooling and heating system.

FIG. 2 is an isometric view of a module from the cooling and heatingsystem of FIG. 1.

FIG. 3 is a schematic view of a first embodiment of a cooling andheating system.

FIG. 4 is a schematic view of a second embodiment of a cooling andheating system.

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to centralized, modular cooling andheating systems that are capable of providing cooling for one or morerefrigeration fixtures, cooling to meet space cooling requirements andself-contained refrigerated fixture condensing water, and heating forvarious facility heating loads such as domestic hot water heating andspace heating. Although not so limited, the centralized, modular coolingand heating systems of the present invention are particularly wellsuited for use in restaurants, cafeterias, and other food servicefacilities having refrigerated fixtures located in their foodpreparation and/or serving areas. As will be described in more detailbelow, most of the system components are combined in one or more modulessited in a centralized location either within or outside of the foodpreparation and serving areas.

Referring to the drawings wherein identical reference numerals denotethe same elements throughout the various views, FIG. 1 shows a modularcooling and heating system having at least one module 2, tworefrigerated loads 3 and a heat sink 4. Typical refrigerated loadsinclude refrigerated fixture cooling coils, HVAC cooling coils, andwater-cooled, self-contained refrigerated fixture condensers. The heatsink 4 can include one or more heating loads or sinks such as domestichot water heating, facility space heating, outdoor air-cooled fluidcoolers, outdoor evaporative fluid coolers, and water-cooled heatexchangers with cooling water supplied by others from building coolertowers or other sources. FIG. 1 shows one module with two refrigeratedloads and one heat sink by way of example only. It should be noted thata heating and cooling system in accordance with the present inventioncan include more than one module in conjunction with any number ofrefrigerated loads and heat sinks.

The module 2 comprises an enclosure 5 containing two interchangeablecartridges 6 and an electrical power and control panel 7. Two cartridgesare shown by way of example only, and it should be noted that adifferent number of cartridges could be used. In the illustratedembodiment, each cartridge 6 supplies chilled fluid to a correspondingone of the refrigerated loads 3 and rejects heat to the heat sink 4.Each cartridge 6 can provide either medium temperature (“MT”) coolingfluid for refrigeration applications or high temperature (“HT”) coolingfluid for space cooling and condensing cooling fluid for low temperaturerefrigerated fixtures with fluid-cooled self-contained refrigerationunits. The terms “medium temperature” and “high temperature” are usedherein in a relative sense only, meaning a high temperature cartridgeprovides chilled fluid at generally higher temperatures than a mediumtemperature cartridge. For example, a medium temperature cartridge mightprovide chilled fluid temperatures in a range of 10-20 degrees F., whilea high temperature cartridge might provide chilled fluid temperatures ina range of 35-50 degrees F.

Referring to FIG. 2, one possible configuration for the module 2 isshown in more detail. In this configuration, the enclosure 5 is avertical cabinet having two support positions or slots 8, one above theother, for interchangeably receiving the cartridges 6. The electricalpower and control panel 7, which includes an electronic controller, islocated above the slots 8. The enclosure 5 includes electricalconnectors (not shown) such as Molex connectors for connecting acartridge 6 to the electrical power and control panel 7 when thecartridge 6 is inserted into one of the slots 8. Each cartridge 6comprises various components mounted on a base plate 9. As described inmore detail below, the components can include one or more compressors, acondenser, an expansion device, a chiller heat exchanger and a pump,plus interconnecting piping and basic electro-mechanical safetycontrols. Also included are connectors (not shown in FIG. 2) for makingfluid connections between module cartridges and system piping andvalving external to the module 2.

The module 2 can use a number of interchangeable cartridges of differentcapacities and application types (e.g., high temperature or mediumtemperature). The cartridges 6 deployed in the module 2 are selectedbased on the heating and cooling load requirements for the facility. Thecartridges are of standard layout and manufacturing design and generallyvary only in the size of the compressor and other major components andthe resulting cooling and heating capacity. Cartridges areinterchangeably disposed in the slots 8. That is, the cartridges 6 canbe easily slid into the slots 8 and also are easily removed, either forservice or for replacement with another cartridge to change theconfiguration or capacity of the module 2.

This arrangement allows for mixing and matching of modules andcartridges to accurately and efficiently meet the full range of heatingand cooling requirements of the facility, from the lowest loadrequirement during periods of facility inactivity to the peakrequirement during periods of high facility usage/activity. For example,depending on required capacity, one or two cartridges 6 are slid intoone or two of the slots 8. When using two cartridges, the module 2 canhave one MT cartridge and one HT cartridge, two MT cartridges, or two HTcartridges, as required by the particular facility loads. As mentionedabove, a modular cooling and heating system may contain as many modulesas required without limit, and each module may contain any combinationof MT and HT cartridges to provide the total capacity and capacitymodulation ability required by the food service facility refrigerationand space cooling needs.

FIG. 3 shows one embodiment of a centralized, modular cooling andheating system 10 including a medium temperature refrigeration circuit12, a medium temperature secondary cooling circuit 14, a hightemperature refrigeration circuit 16, a high temperature secondarycooling circuit 18, and a heating circuit 20. As used herein, a “hightemperature circuit” generally operates at a higher temperature than a“medium temperature circuit.”

The medium temperature refrigeration circuit 12 includes a compressor22, a condenser 24 (having first and second inlets 26 and 28 and firstand second outlets 30 and 32), an expansion device 34, and a chillerheat exchanger 36 (having first and second inlets 38 and 40 and firstand second outlets 42 and 44), all connected together, in the orderrecited, in closed-loop, serial flow communication. The mediumtemperature refrigeration circuit 12 is charged with a suitablerefrigerant that is compressed in the compressor 22. Compressedvapor-phase refrigerant is discharged to the first inlet 26 of thecondenser 24, where it is cooled and condenses. Liquid refrigerantdischarged from the first outlet 30 of the condenser 24 flows throughthe expansion device 34, expanding while it does so. The refrigerantexits the expansion device 34 and flows through the chiller heatexchanger 36, entering via the first inlet 38 and exiting from the firstoutlet 42. The refrigerant exits the chiller heat exchanger 36 in asuperheated gaseous state and flows back to the inlet of the compressor22 via a suction line 46, where the cycle is repeated.

The medium temperature secondary cooling circuit 14 includes the chillerheat exchanger 36 (which is a part of both the medium temperaturerefrigeration circuit 12 and the medium temperature secondary coolingcircuit 14), a pump 48 and a cooling coil 50 all connected together, inthe order recited, in closed-loop, serial flow communication. Asdepicted by dashed line in FIG. 3, the compressor 22, the condenser 24,the expansion device 34, the chiller heat exchanger 36 and the pump 48make up a medium temperature cartridge 6′. The medium temperaturesecondary cooling circuit 14 is charged with a suitable coolant fluid,such as a propylene glycol-water solution or the like. Coolant passesthrough the chiller heat exchanger 36, entering via the second inlet 40and exiting from the second outlet 44, where it is cooled by therefrigerant that is also passing through the chiller heat exchanger 36.That is, heat is transferred from the coolant to the refrigerant in thechiller heat exchanger 36. As depicted in FIG. 3, the chiller heatexchanger 36 has a counter-flow design in which the coolant and therefrigerant flow in opposite directions through the chiller heatexchanger 36 to optimize heat transfer. The coolant is pumped via thepump 48 to the cooling coil 50. It should be noted that while FIG. 3shows the pump 48 as being on the outlet side of the chiller heatexchanger 36, the pump 48 alternatively could be located on the inletside of the chiller heat exchanger 36. The cooling coil 50 is deployedto provide cooling to any suitable cooling load. For example, thecooling coil 50 could be deployed in a refrigerated fixture located in afood preparation or serving area of a food service facility for coolingthe refrigerated compartment(s) thereof.

The high temperature refrigeration circuit 16 (which is similar to themedium temperature refrigeration circuit 12 but operates at a highertemperature as mentioned above) includes a compressor 52, a condenser 54(having first and second inlets 56 and 58 and first and second outlets60 and 62), an expansion device 64, and a chiller heat exchanger 66(having first and second inlets 68 and 70 and first and second outlets72 and 74) all connected together, in the order recited, in closed-loop,serial flow communication. The high temperature refrigeration circuit 16is charged with a suitable refrigerant that is compressed in thecompressor 52. Compressed vapor-phase refrigerant is discharged to thefirst inlet 56 of the condenser 54, where it is cooled and condenses.Liquid refrigerant discharged from the first outlet 60 of the condenser54 flows through the expansion device 64, expanding while it does so.The refrigerant exits the expansion device 64 and flows through thechiller heat exchanger 66, entering via the first inlet 68 and exitingfrom the first outlet 72. The refrigerant exits the chiller heatexchanger 66 in a superheated gaseous state and flows back to the inletof the compressor 52 via a suction line 76, where the cycle is repeated.

The high temperature secondary cooling circuit 18 includes the chillerheat exchanger 66 (which is a part of both the high temperaturerefrigeration circuit 16 and the high temperature secondary coolingcircuit 18), a pump 78 and a cooling coil 80 all connected together, inthe order recited, in closed-loop, serial flow communication. Asdepicted by dashed line in FIG. 3, the compressor 52, the condenser 54,the expansion device 64, the chiller heat exchanger 66 and the pump 78make up a high temperature cartridge 6″. The high temperature secondarycooling circuit 18 is charged with a suitable coolant fluid, such as apropylene glycol-water solution or the like. Coolant passes through thechiller heat exchanger 66, entering via the second inlet 70 and exitingfrom the second outlet 74, where it is cooled by the refrigerant that isalso passing through the chiller heat exchanger 66. That is, heat istransferred from the coolant to the refrigerant in the chiller heatexchanger 66. Like the previously-mentioned chiller heat exchanger 36,the chiller heat exchanger 66 can employ a counter-flow design. Thecoolant is pumped via the pump 78 to the cooling coil 80. It should benoted that while FIG. 3 shows the pump 78 as being on the outlet side ofthe chiller heat exchanger 66, the pump 78 alternatively could belocated on the inlet side of the chiller heat exchanger 66. The coolingcoil 80 is deployed to provide cooling to any suitable cooling load. Forexample, the cooling coil 80 could be deployed as a part of the HVACsystem of a facility to provide air conditioning for the facility. Thecooling coil 80 could be deployed to a condenser for a low temperaturerefrigerated fixture located in the facility.

The heating circuit 20 accepts heat rejected from the refrigerationcircuits 12 and 16 and uses this heat for various heating demandsthroughout a facility, such as space heating, domestic hot water heatingand the like. The heating circuit 20 is charged with a suitable heattransfer fluid such as a propylene glycol-water solution or the like andincludes the condensers 24 and 54 and two heating loads, a hydronicheating system 82 and a domestic hot water heater 84, in flowcommunication with the condensers 24 and 54. The two heating loadsdepicted in FIG. 3 are shown by way of example only, as different typesand combinations of heating loads, including a single heating load,could be used. A fluid cooling loop including the condensers 24 and 54and a fluid cooler 86 (having an inlet 88 and an outlet 90) in flowcommunication with the condensers 24 and 54 is provided in parallel tothe heating circuit 20. A pump 92 is provided for circulating heattransfer fluid between the condensers 24 and 54 and the heating loads 82and 84 and/or the fluid cooler 86. The fluid cooler 86 can comprise anysuitable implementation, such as an air-cooled fluid cooler, anevaporative fluid cooler, a cooling tower, cooling tower water orchilled water from a third party source, and the like.

The heating circuit 20 further includes a pair of heat reclamationvalves 94 and 96, which are both three-way valves that can be operatedto selectively direct heat transfer fluid discharged from the secondoutlets 32, 62 of the condensers 24 and 54 to the heating loads 82 and84 and/or the fluid cooler 86. Heat reclamation valve 94 has an inlet 98connected to the second outlet 32 of the condenser 24, and the otherheat reclamation valve 96 has an inlet 100 connected to the secondoutlet 62 of the condenser 54. Each of the heat reclamation valves 94and 96 has a first outlet 102, 104 connected to the heating loads 82 and84 and a second outlet 106, 108 connected to the inlet 88 of the fluidcooler 86. The heat reclamation valves 94 and 96 can be of the on/offtype, where all of the fluid entering the inlet is discharged throughone or the other of the two outlets so that all of the fluid is directedto either the heating loads 82 and 84 or the fluid cooler 86.Alternatively, the heat reclamation valves 94 and 96 can be of themodulating type where the fluid entering the inlet can be split betweenthe two outlets. In this case, a first portion of the fluid entering theinlet is directed to the heating loads 82 and 84 and a second portion ofthe fluid is directed to the fluid cooler 86. The pump 92 circulatesheat transfer fluid through the condensers 24 and 54, through the heatreclamation valves 94 and 96, and to the heating loads 82 and 84 and/orthe fluid cooler 86, depending on the settings of the valves 94 and 96.Heat is transferred to the heat transfer fluid in the condensers 24 and54, and heat is transferred from the heat transfer fluid in the heatingloads 82 and 84 and/or the fluid cooler 86.

The heating circuit 20 also includes a return control valve 110 thatselectively returns heat transfer fluid discharged by the heating loads82 and 84 either directly to the condensers 24 and 54 or first to thefluid cooler 86 and then to the condensers 24 and 54. The return controlvalve 110 is a three-way valve having an inlet 112 connected to theheating load discharge, a first outlet 114 connected to the inlet of thepump 92 and a second outlet 116 connected to the inlet 88 of the fluidcooler 86. Like the heat reclamation valves 94 and 96, the returncontrol valve 110 can be of the on/off type or the modulating type.Generally, if the heat transfer fluid returning from the heating loads82 and 84 is sufficiently cool (i.e., as cool as necessary for currentcondenser operating conditions), then the return control valve 110 willbe operated to direct the heat transfer fluid directly to the condensers24 and 54. If the heat transfer fluid returning from the heating loads82 and 84 is not sufficiently cool, then the return control valve 110will be operated to direct the heat transfer fluid to the fluid cooler86, where the heat transfer fluid will be further cooled before flowingto the condensers 24 and 54.

Referring to FIG. 4, another embodiment of a modular cooling and heatingsystem 10′ is shown. The cooling and heating system 10′ is similar tothe cooling and heating system 10 of FIG. 3 in that it includes a mediumtemperature refrigeration circuit 12, a medium temperature secondarycooling circuit 14, a high temperature refrigeration circuit 16, a hightemperature secondary cooling circuit 18, and a heating circuit 20having a fluid cooling loop. These elements are essentially the same asthe corresponding elements in the cooling and heating system 10 of FIG.3, which are described above, and are thus not described in detailagain.

The cooling and heating system 10′ of FIG. 4 further includes a “heatpump” circuit 118 for extracting heat from outdoor ambient air. The heatpump circuit 118 includes a heat exchanger 120 (having first and secondinlets 122 and 124 and first and second outlets 126 and 128) and a heatpump control valve 130. The heat pump control valve 130 is a three-wayvalve having an inlet 132 connected to the outlet 90 of the fluid cooler86, a first outlet 134 connected to the first inlet 122 of the heatexchanger 120, and a second outlet 136 connected to the pump 92. Theheat pump control valve 130 can be of the on/off type or the modulatingtype and is operated to direct heat transfer fluid discharged from thefluid cooler 86 through the heat exchanger 120. The first outlet 126 ofthe heat exchanger 120 is connected to the inlet 88 of the fluid cooler86 via a pump 138, although the pump 138 alternatively could be locatedon the outlet side of the fluid cooler 86.

The second inlet 124 of the heat exchanger 120 is connected to receivechilled coolant from the medium temperature secondary cooling circuit14. Specifically, a portion of the chilled coolant is diverted from themedium temperature secondary cooling circuit 14 upstream of the coolingcoil 50 to the second inlet 124 of the heat exchanger 120, while theremainder of the chilled coolant flows to the cooling coil 50. Thiscould be accomplished in a number of ways, such as providing a divertingvalve upstream of the cooling coil 50. The diverted portion of thechilled coolant passes through the heat exchanger 120 and is heated bythe heat transfer fluid also passing through the heat exchanger 120. Thecoolant exits the heat exchanger 120 through the second outlet 128 andis returned to the medium temperature secondary cooling circuit 14,between the cooling coil 50 and the chiller heat exchanger 36. Heatingthe coolant in this manner increases the cooling load on the mediumtemperature secondary cooling circuit 14, which causes the mediumtemperature secondary cooling circuit 14 to do more work and presentmore heat to the condenser 24 of the medium temperature refrigerationcircuit 12. This additional heat is then available to be recovered bythe heating circuit 20. Heat pump capacity can be further increased bydriving the chilled coolant temperature of the medium temperaturesecondary cooling circuit 14 lower and lower, thereby reducingefficiency and causing the compressor 22 of the medium temperaturerefrigeration circuit 12 to work harder and put more heat into thesystem. At some point, like all heat pump systems, the efficiency willapproach the efficiency of electric heat, suggesting a switch to backupelectric resistance or gas-fired fluid heaters. The heat pump circuit118 would be most beneficial in locations where outside ambienttemperatures are such that a space heating requirement greater than whatcan be met with normal system operation would occur a relatively lownumber of hours per year.

While specific embodiments of the present invention have been described,it should be noted that various modifications thereto can be madewithout departing from the spirit and scope of the invention as definedin the appended claims.

1. A module for use in a cooling and heating system, said modulecomprising: an enclosure having a number of cartridge-receiving slots;an electronic controller mounted to said enclosure; and a cartridgeinterchangeably disposed in a first one of said cartridge-receivingslots so as to make an electrical connection with said electroniccontroller, wherein said cartridge includes a compressor, a condenserand a chiller heat exchanger.
 2. The module of claim 1 wherein saidcompressor, said condenser and said chiller heat exchanger are mountedon a base plate.
 3. The module of claim 2 wherein said cartridge furtherincludes an expansion device and a pump mounted on said base plate. 4.The module of claim 1 further comprising a further cartridgeinterchangeably disposed in a second one of said cartridge-receivingslots so as to make an electrical connection with said electroniccontroller, wherein said further cartridge includes a compressor, acondenser and a chiller heat exchanger.
 5. The module of claim 1 whereinsaid enclosure is a vertical cabinet.
 6. A modular cooling and heatingsystem comprising: at least one module, said module comprising anenclosure having a number of cartridge-receiving slots; an electroniccontroller mounted to said enclosure; and a cartridge interchangeablydisposed in a first one of said cartridge-receiving slots so as to makean electrical connection with said electronic controller, wherein saidcartridge includes a compressor, a condenser and a chiller heatexchanger; a refrigerated load wherein said cartridge supplies chilledfluid to said refrigerated load; and a heat sink wherein said cartridgerejects heat to said heat sink.
 7. The modular cooling and heatingsystem of claim 6 further comprising: a second cartridge interchangeablydisposed in a second one of said cartridge-receiving slots so as to makean electrical connection with said electronic controller, wherein saidsecond cartridge includes a compressor, a condenser and a chiller heatexchanger; and a second refrigerated load wherein said second cartridgesupplies chilled fluid to said second refrigerated load.
 8. The modularcooling and heating system of claim 7 wherein said second cartridgerejects heat to said heat sink.
 9. The modular cooling and heatingsystem of claim 7 further comprising a second heat sink, wherein saidsecond cartridge rejects heat to said second heat sink.
 10. The modularcooling and heating system of claim 6 wherein said refrigerated load isselected from the group consisting of refrigerated fixture coolingcoils, HVAC cooling coils, and water-cooled, self-contained refrigeratedfixture condensers.
 11. The modular cooling and heating system of claim6 wherein said heat sink is a heating load selected from the groupconsisting of domestic hot water heating, facility space heating,outdoor air-cooled fluid coolers, outdoor evaporative fluid coolers, andwater-cooled heat exchangers.
 12. A modular cooling and heating systemcomprising: a first refrigeration circuit charged with a refrigerant andcomprising a first compressor, a first condenser, a first expansiondevice, and a first heat exchanger all connected together in series flowcommunication; a first secondary cooling circuit charged with a coolantand comprising said first heat exchanger, and a first cooling coil allconnected together in series flow communication, wherein heat istransferred from said coolant to said refrigerant in said first heatexchanger; and a heating circuit charged with a heat transfer fluid andcomprising said first condenser, at least one heating load, and a pumpfor circulating said heat transfer fluid between said first condenserand said heating load, wherein heat is transferred to said heat transferfluid in said first condenser and heat is transferred from said heattransfer fluid in said heating load.
 13. The modular cooling and heatingsystem of claim 12 further comprising: a second refrigeration circuitcharged with a refrigerant and comprising a second compressor, a secondcondenser, a second expansion device, and a second heat exchanger allconnected together in series flow communication; a second secondarycooling circuit charged with a coolant and comprising said second heatexchanger, and a second cooling coil all connected together in seriesflow communication, wherein heat is transferred from said coolant ofsaid second secondary cooling circuit to said refrigerant of said secondrefrigeration circuit in said second heat exchanger; and wherein saidheating circuit further comprises said second condenser and said pumpalso circulates said heat transfer fluid between said second condenserand said heating load, and wherein heat is transferred to said heattransfer fluid in said second condenser.
 14. The modular cooling andheating system of claim 13 wherein said first refrigeration circuitoperates at a higher temperature than said second refrigeration circuit.15. The modular cooling and heating system of claim 12 furthercomprising: a fluid cooler having an inlet and an outlet, said outlet ofsaid fluid cooler being connected to an inlet of said first condenser;and a first three-way valve having an inlet connected to an outlet ofsaid first condenser, a first outlet connected to said heating load, anda second outlet connected to said inlet of said fluid cooler, said firstthree-way valve being able to selectively direct heat transfer fluidbeing discharged from said outlet of said first condenser to saidheating load and/or said fluid cooler.
 16. The modular cooling andheating system of claim 15 further comprising: a third heat exchangerhaving first and second inlets and first and second outlets, said firstoutlet of said third heat exchanger being connected to said inlet ofsaid fluid cooler, said second inlet of said third heat exchanger beingconnected to receive coolant diverted from said first secondary coolingcircuit, and said second outlet of said third heat exchanger beingconnected to return coolant to said first secondary cooling circuit; anda second three-way valve having an inlet connected to said outlet ofsaid fluid cooler, a first outlet connected to said first inlet of saidthird heat exchanger, and a second outlet connected to said inlet ofsaid first condenser, said second three-way valve being able toselectively direct heat transfer fluid being discharged from said outletof said fluid cooler to said third heat exchanger and/or said firstcondenser.
 17. The modular cooling and heating system of claim 16further comprising a pump for circulating said heat transfer fluidthrough said third heat exchanger and said fluid cooler.
 18. The modularcooling and heating system of claim 12 wherein said heating load is ahydronic heating system.
 19. The modular cooling and heating system ofclaim 12 wherein said heating load is a hot water heater.